Let's start at the beginning...

What plane?
What motor? (with specs)
What ESC(s)? (with specs)
What battery(ies)? (with specs)

The first thing is to find out exactly how much current is going to be pulled from the battery.

Actually I've never used a switch to pass more than just a few amps. If I need to pass more current I'll have a switch operate a relay which will then pass the current.

I really need more information and then time to think about this more throughly.